[llvm] [PowerPC][GlobalMerge] Reduce TOC usage by merging internal and private global data (PR #101224)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-x86_64-debian-dylib` running on `gribozavr4` while building `llvm` at step 7 "test-build-unified-tree-check-llvm".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/60/builds/4942

Here is the relevant piece of the build log for the reference:
```
Step 7 (test-build-unified-tree-check-llvm) failure: test (failure)
******************** TEST 'LLVM :: ExecutionEngine/JITLink/AArch64/ELF_relocations.s' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: rm -rf /b/1/llvm-x86_64-debian-dylib/build/test/ExecutionEngine/JITLink/AArch64/Output/ELF_relocations.s.tmp && mkdir -p /b/1/llvm-x86_64-debian-dylib/build/test/ExecutionEngine/JITLink/AArch64/Output/ELF_relocations.s.tmp
+ rm -rf /b/1/llvm-x86_64-debian-dylib/build/test/ExecutionEngine/JITLink/AArch64/Output/ELF_relocations.s.tmp
+ mkdir -p /b/1/llvm-x86_64-debian-dylib/build/test/ExecutionEngine/JITLink/AArch64/Output/ELF_relocations.s.tmp
RUN: at line 2: /b/1/llvm-x86_64-debian-dylib/build/bin/llvm-mc -triple=aarch64-unknown-linux-gnu -x86-relax-relocations=false    -position-independent -filetype=obj -o /b/1/llvm-x86_64-debian-dylib/build/test/ExecutionEngine/JITLink/AArch64/Output/ELF_relocations.s.tmp/elf_reloc.o /b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/test/ExecutionEngine/JITLink/AArch64/ELF_relocations.s
+ /b/1/llvm-x86_64-debian-dylib/build/bin/llvm-mc -triple=aarch64-unknown-linux-gnu -x86-relax-relocations=false -position-independent -filetype=obj -o /b/1/llvm-x86_64-debian-dylib/build/test/ExecutionEngine/JITLink/AArch64/Output/ELF_relocations.s.tmp/elf_reloc.o /b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/test/ExecutionEngine/JITLink/AArch64/ELF_relocations.s
RUN: at line 4: /b/1/llvm-x86_64-debian-dylib/build/bin/llvm-jitlink -noexec               -abs external_data=0xdeadbeef               -abs external_func=0xcafef00d               -check /b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/test/ExecutionEngine/JITLink/AArch64/ELF_relocations.s /b/1/llvm-x86_64-debian-dylib/build/test/ExecutionEngine/JITLink/AArch64/Output/ELF_relocations.s.tmp/elf_reloc.o
+ /b/1/llvm-x86_64-debian-dylib/build/bin/llvm-jitlink -noexec -abs external_data=0xdeadbeef -abs external_func=0xcafef00d -check /b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/test/ExecutionEngine/JITLink/AArch64/ELF_relocations.s /b/1/llvm-x86_64-debian-dylib/build/test/ExecutionEngine/JITLink/AArch64/Output/ELF_relocations.s.tmp/elf_reloc.o
Expression 'decode_operand(test_adr_gotpage_external, 1) =      (got_addr(elf_reloc.o, external_data)[32:12] -         test_adr_gotpage_external[32:12])' is false: 0x108 != 0xffffffffffe00108
/b/1/llvm-x86_64-debian-dylib/build/bin/llvm-jitlink: Some checks in /b/1/llvm-x86_64-debian-dylib/llvm-project/llvm/test/ExecutionEngine/JITLink/AArch64/ELF_relocations.s failed

--

********************


```

https://github.com/llvm/llvm-project/pull/101224